Non-sagging loading dock canopy frame



June 24, 1958 E. P. DAZZO 2,340,091

NON-SAGGING LOADING DOCK CANOPY FRAME Filed July 16. 1952 2 Sheets-Sheet l E i g June 24, 1958 E. P. D'AZZO NON-'SAGGING LOADING DOCK CANOPY FRAME Filed July 16; 1952 2 SheetsSheet 2 United States Patent NON-'SAGGING 'LOADING DOCK CANOPY Errol P. .DAzzo, vBrooklyn,N. Y.

Application July16, 1952, Serial No. 299,205 4 Claims. c1. 135-5 This invention relates 'to an improved folding canopy or rain covering for protecting-the passage established between a freight car and theentrance of a building or warehouse during the movement of-freight or goods from the freight car to the building or from the building to the freight car during rainfall or otherwise, 'as-during a heat period.

Various attempts havesbeen made to provide adequate protection between-th'ebuilding entrance and the side or other door of the freight car, but due to various difiiculties maximum service for all purposes has not been provided by constructions offered for public use.

One of the objects of the invention is the provision of a foldable canopy having collapsible twin side frames, so constructed with end toggles, that a stable horizontal open position of the frames may be established, and a compact folded position for all frames and the canopy covering may be obtained when the frames are folded against the building wall.

Another object of the invention is the provision of a folda-ble canopy having a rain collecting pan supported in its open position under the gap between the canopy and the freight car entrance or door way, which is adjustable to the width of the canopy and adjustable vertically to receive water dripping over the door way of the freight car. Y

Another object of the invention is the provision of a rain covering for loading docks and the like, which is equipped with pulley guided cables for collapsing the frame to closed position, and with-means operated by the canvas winding drum for operating the cables.

' Another object of the invention is to provide a main rear link of the scissor arm or lazy-tong system with anoffset forming a part of the rear toggle, so thatcom-pact folding of all links against the building wall may be obtained, while the toggle and this construction will aid to maintain the front frame in full side engagement with the freight car.

A still further object of the invention is the provision of a folding canopy frame with toggle links preassembled by a tubular rivet, 'so arranged that the links may be easily mounted on a previously secured stud on a building wall, by a workman operating on a high ladder, at the lowest possible labor cost. I

With the above and other objects in view, the invention comprises certain new and useful constructions, combinations and arrangements of parts, clearly described in the following specifications, and fully illustrated in the drawings which accompany the specifications, and in which: 7

Fig. 1 is a top plan view, showing the relativepositions of the collapsible and non-sagging canopy, the building entrance and the railroad freight car.

Fig. 2 is an isometric view, showing the folding canopy frame in open position and illustrating the approximate position of the rain drip pan.

Fig. 3 is a detail fragmentary side view, showing the toggle system of links in open position.

the scissor arm collapsed Fig. 4 is a side elevation, showing the upper and lower scissor or lazy-tong arms in extended open positions, the protecting side canvas being left out for convenience.

Fig. 5 is an end elevation, showing the canopy in-ope n' position against a freight car.

Fig. 6 is a side elevation, partly broken away, showing with the front frame partly collapsed. i

Fig. 7 is a fragmentary sectional view, showing a tubular rivet coupling for the double links of the toggle.

Fig. 8 is a detail horizontal sectional view enlarged showing the double toggle links and the next links in-sec-- tion.

Fig. 9 is a detail sectional view, enlarged, of the clamp forthe end of the drip pan.

Fig. 10 is a bottom plan view of the drip pan.

Fig. 11 is another side elevation of the scissor arm, shown collapsed, on a reduced scale.

Fig. 12 is a detail side view of a bracket.

Fig. 13 is a detail plan view of an expansible drip pan,

provided with vertical and horizontal sliding adjustment.

Fig. 14 is an end elevation thereof. Referring to the accompanying drawing, which illustrates the practical embodiment-of the invention, '10 designates the collapsible canopy cover, which is supported onthe side building wall 11, to bridge the open space betweenthis wall and the freight car 12, which operates on the track 13. A loading board 14 is placed across the threshold or platform board 15 of the building and engages the'floor of the freight car, in the usual manner.

On the opposite sides of the building entrance 16 the posts 17 and 18 are secured by bolts 19 to the wall 11, which may be of any construction. These posts are shown to be of-angle shape, or L-shaped, to provide a rear attaching wall or flange 20 and a forward holding flange or wall 2051. The two posts are mounted in par allel relation to each other.

On the flange 20a of the post 17 an upper scissor arm or lazy-tong arm 21 and a lower scissor arm or lazy-tong arm 22 is supported, the latter under the former. These arms are duplicates of each other and only one need be described. On the post 18 a pair of similar arms are mounted, one above the other.

Each scissor or lazy-tong arm includes a series of links '25, 26,127 and 28, and another series of links 30, 31, 32, 33 and 34. The link 26 is double and is rearwardly oifset at 26a and is provided with a long lower lever arm 26b1anda shorter upper lever ar-m 26c, offset relative to the lower lever arm 26b. The upper end of the link 25 is pivotally connected at 25:: with the double link 26, and this pivot is the dividing line between the upper lever arm 26c and the lower lever arm 26b. The upper short lever arm 26c is formed with a series of spaced holes 26d and a -bol t or pin 26e extends through one of these holes to slidably engage the longitudinal slot 35:: of the block 35, which is longitudinally adjustable on the linkbar 36, the-rear end .of which is pivoted on the bolt or pin 36a. on the outer flange 20a of the'supporting post 1'7 Thelink 25'is pivotally connected by the pin or bolt 25b to the flange 20a of the post 17, and on this pin or 'bolt the double .short links 30 are pivotally supported.

The outer ends of the double links 30 are pivotally connected by the pin or bolt 3011 with the lower end of the link 31. The link 31 is pivotally connected at 31a with the link 26. The lower end of the link 26 is pivotally connected at 27:: with the link 27, and the link 27 is pivotally connected between its ends with the link 32 at 27b, and the upper end of the link 31 is pivotally connected at 31b with the upper end of the link 32. The lower end of the link 32 is pivotally connected at 32a with the lower end of the link 33, which is pivotally'connected between its ends with the link 28. at 28b, and the Patented June 24, 1958 upper end of the link 28 3 is pivotally connected at 28:; with the upper portion of the link 27. The lower end of the link 28 is pivotally connected at 29a with the horizontal link 29, and the upper end of the link 33 is pivotally'connected at 33a with the upper'end of the link 34, which is shorter thanthe link 28 and disposed in non-parallel relation thereto, and the lower end of the short link 34 is pivotally connected at 34a with the horizontal link 29, forward of the link connection 28a with the link 28. The forwardend of the link 29 is pivoted at 290 to the post 38. The block 35 is provided with tion on the bar link 36.

, across the rear posts, and the top cover sheet 52 of the The links 25, 26, 27, 28 constitute a flexible pivoted pressure system for actingon the horizontal terminal link 29, and one half of the multiple scissor or lazy-tong system, the other half being made up of the links30; 31, 32, 33 and 34. The double links 30-together with the longer rear links 25, 26 and 31 constitute a toggle pressure link system, which operates on the two scissor link series to maintain the lazy-tong arm in extended open position, against sagging, in .a horizontal plane, or any plane inclined thereto.

In its open position asshown in Fig. 4, each collapsible arm is maintained in, non-sagging horizontal position by means of thetoggle link system, and in this condition the short links 30 are arranged in axial alignment with the link 31. But when the frame arm is foldedthe short double links swing downwardly on the pivot bolt 25b, thus causing the double channel links 26 to swing closer to the supporting post 17. By adjusting the pivot connection at 26e'with the slot 35a of the adjustable block 35, the plane of opening of the flexible or lazy-tong arm may be varied.

When the flexible arm is collapsed the offset upper short lever arm 260 will assume an extreme rearward position against the post or near it, swinging the block 35 into a nearly'vertical position. the other links of the arm will assume a nearly vertical plane position, as shown in Fig. 6.

. The horizontal terminal link 29 of each lazy-tong supporting arm is pivotally connected at'its outer end with a vertical frame bar 38, of angle construction. The. two frame bars 38 are rigidly connected withthe ends of the upper cross bar 39, and with the ends of the lower cross bar 40. The two frame bars, 38 and the cross bars 39 .and 40 thus forming a rectangular. open frame wholly supported by the four lazy-tongs arms, two on each side of this forward'and open frame.

The connection between each end of the cross bars and the vertical frame bar is made by means of. a fitting 41, which includes a tubular socket 41a which receives the end of the cross bar, and an integral cast arm 41b, which is provided with a seat 41c to engage the end of the angle bar, to which it is secured by means of the bolt or screw 42. The cross bars are pipe or tubular stock, so as to be easily available and light, and easily cut, and have a telescopic fit in the sockets 4111. To compensate for adjustments, and to prevent end play and noise, the socket 41a is provided with a set screw 410 for clamping the tubular bar inthe socket. i

The collapsible arms are folded against the building wall by means of a cable 43 arranged to work over guide pulleys on each side of the composite frame. Each cable 43 has a lower horizontal run 43a, the rear end of which is secured to the building wall or to the nearest post at 43b. This run is held in place by means of the pulley 44, secured to the vertical frame bar 38, and the cable is then extended vertically and engages the pulley 45 also secured to the frame bar 38. The cable 43 is then exr tended rearwardly and on the outside of the uppercollapsib le arm engages the pulley 46, attached to the building wall or to the rear post, and then engages the winding In this folded position.

.to the same section.

fabric or canvas cover for the frame, is connected with this bar. This top sheet engages the roller or bar 27m on the extension 27!! of the link 27, and then extends in an approximate horizontal, plane to engage the top cross bar 39 of the front frame bars 38. Side curtain walls 53 are stitched to the side edges of the sheet 52, and are formed so that the entire cover, comprising the top sheet 52 and the side curtain sheets 53 will have an accordion folding action, as indicated in the drawing.

The cable 43 is connected on the outside of the upper and lower scissor arms, so that the side curtains 53 will not be cut or mutilated by the action of the scissor links on each other, the cable runs spacing the curtain walls 53 from the links to prevent lateral bulging between links in the opening and closing movements of the arms.

The two cables 43 on opposite sides of the frame may be wound simultaneously when the wheels or winding drum 47 is manually turned, and when this is done the accordion fabric will collapse against the arm, and at the same time protect the collapsed arms from rain and dust.

The protective canopy frame and its fabric cover, is constructed wider than any standard freight car entrance, so that coverage of the entrance may be made when the car fails to stop in alignment with the building entrance, or to one sidethereof, or out of line with it.

When the front frame is in pressure engagement with the side of the freight car, a small space is left between the front frame and the side of the freight car, and during a rainfall rain water will drip through this space into the car or upon the men working through the covered passage, or upon the goods being handled.

To prevent this water drip from interfering with the work and damaging goods, I provide a rain collecting drippan 55, which includes the sliding sections 55a and 55b, which by telescopic sliding on each other may be expended or contracted. Each pan section is secured inplace on its nearest vertical frame bar 38, by means of the clamp 56, which consists of a member 57 secured to the end of the section and a member 57a also secured A thumb or wing screw 58 is threaded through the two sections to clamp the inner flange of the adjacent post or bar ,38. By varying the location of the clamping action one end of the drip pan may be mounted in a lower plane than the other, and any desired vertical adjustment of the pan may be made. A drain tube 59 is secured to the pan at one end, and may be connected with a hose 59a to carry the drip away.

The double links 30 are pre-assembled by means 'of a tubular rivet 30h, which is extended through the pivot holes of one end of each link and flanges at its ends, a spacing washer 30 being arranged between the links. Through this tubular rivet the supporting pivot bolt for the links 30 is extended, after this bolt 25b has been attached to the supporting flange 20a of the rear post. The ends of the tubular rivet are flanged against the outer sides of the links 30 at 30k. By this arrangement the two links are assembled so that their inner bearing holes are maintained in axial alignment. On the outer supporting flange 20a of the post, the stud 25b is mounted on the flange 20a to support the links 30. This stud is formed with a thrust collar 3011, which engages the side of the flange 20a, and receives the nut 30p, which clamps the stud on the flange 20a. The tubular rivet 30h with the links 30 are then mounted on the stud and another nut 30r is threaded on the stud to hold the links on the same for service operation.

When the stud 25b is positioned or clamped to the vertical post or bar, the workman; who must operate on a high ladder without the aid of ahelper, can quickly slip both short links on the stud, and when they are mounted in place it is then easy to tighten a holding nut thereon, to make the assembly permanent. On the other hand without the aid of the tubular washer this would be very diflicult, as onejj-nk would easily get out of line position with the other and considerable time would be lost, which would increase the cost of making the required job installation.

By using two rigid angle iron rear posts, positive parallel spacing and easy mounting is accomplished. If the wall construction is defective in one place a secure anchor for the holding bolt may be found in another place. By using a gauge stick equal parallel spacing is made, and by using any vertical locating system, vertical alignment is gained.

However, when the job requirement calls for it, a. bracket 60, having a single pivot 61 for the links, may be used, as shown in Fig. 12.

The block 35 is adjustably secured to the link bar 36, and the link 26 has a sliding movement on the block 35, due to the slot 35a, which receives the pivot of the link 26. This construction adds flexibility to the toggle links system, and permits all of the links to fold snugly against the building wall, so that compact folding of the canvas canopy is obtained. This compact folding is materially aided by the rearward offsetconstruction of the link 26, and the sliding action of this offset upper arm with the block 35. Due to .the series of holes in the link 26 the pitch or the level of the open scissor arm may be varied.

The problem of preventing sagging of the folding scissor arms, and of adjusting their outer positions relative to the horizontal plane, or to maintain them in a horizontal plane, has been an elusive one, but with the toggle link system disclosed, a rear lifting pressure is maintained on the extended scissor arm, which effectively prevents sagging.

Maximum toggle link pressure is obtained when the short links 30 assume an axial relation to the connected links 31. This action tends to force the rear end of the link 31 in an upward position, and to swing the upper end of the link 31 in a forward and downward position or movement. At the same time the link 25 forces the upper short lever of the link 26 in an upward and forward movement, and the longer lower lever arm in a rearward and downward movement. The upper end of the link 31 thus moves downwardly while the lower end of the link 26 moves upwardly, thereby projecting the entire scissor arm forwardly in a horizontal plane, so'that the terminal link 29 will assume an approximate horizontal position when the scissor arm is fully opened.

In its open position the pivot 26:: of the link 26 engages the forward end of the slot 35a, and is thereby limited from further sliding movement on the block 35. It is obvious that by adjusting the position of the block 35 on the link bar 36, the timing of this stop may be varied, with reference to the opening action of the scissor arm.

In Figs. 13 and 14 I show an expansible drip pan 69 which can be constructed of rubberized fabric formed with a series of transverse corrugations and having integral upstanding end walls. This elastic and expansive drip pan is supported on parallel angle bars 62 which are clamped at their ends to the frame posts or bars 38 by the clamping screws 63. The drip pan 60 is 'slidable horizontally on the angle bars 62. This drip pan may be shifted longitudinally from either end to position the pan on the bars 62 and the pan can be compressed or expanded so that it will register with the door opening of a freight car.

- eachside of the-doorway, each arm consisting of an upper first link with one end'pivoted to the support, a lower second link, a short third link, the lower second link and the short third link having a common pivot connection with the support, a fourth link pivoted to the outer end of the short third link, and a fifth link pivotally connected with the outer end of the second link and an outer portion of the fourth link, an inner end portion of i the fifth link having a sliding and pivotal connection with the first link so that each lazy tong arm can be extended and retracted and thus extend and retract the canopy supported thereby.

2. In a loading dock canopy in combination: a pair of spaced vertical supports for said canopy, a pair of lazy tong arms, each of said-arms comprising an upper first link with one end pivoted to one of said supports, a lower second link, a short third link, the lower second link and the short third link having a common pivot connection with said onesupport, a fourth link pivoted to the outer end of the short third link, and a fifth link pivotally connected with the outer end of the second link and an outer portion of the fourth link, an inner end portion of the fifth link having a sliding and pivotal connection with the first link so that each lazy tong arm can be extended and retracted; a rectangular frame secured to the outer free ends of said arms and a flexible fabric sheet connected between said spaced supports and said frame, whereby extension and retraction of said lazy tong arms extends and retracts said flexible sheet.

3. In a loading dock canopy, the combination according to claim 2, further comprising an expansible and contractable drip pan carried by said rectangular frame and adjustably positionable thereon.

4. In a loading dock canopy, the combination according to claim 3, wherein said drip pan is formed of fabric having transverse corrugations and upstanding side walls.

References Cited in the file of this patent UNITED STATES PATENTS 204,187 Bloom May 28, 1878 289,174 Taylor Nov. 27, 1883 549,565 Fultz et al. Nov. 12, 1895 1,092,496 Lockwood Apr. 7, 1914 1,109,038 Burns Sept. 1, 1914 1,736,250 Cameron Nov. 19, 1929 1,841,278 Dallas Jan. 12, 1932 2,294,835 Dazzo Sept. 1, 1942 2,486,170 Kavanaugh Oct. 25, 1949 2,560,466 Meinke July 10, 1951 2,567,995 Eshnaur Sept. 18,1951 

